Developer tray and supply tank assembly



Aug. 19, 1969 E. TIGER ETAL .3,461,788 l DEVELPER TRAY AND SUPPLY TANKASSEMBLY I 4 Filed oct. 23, 1965 /9 ZIJ 1 N VEN TOR5 /fwverA//e Qs/cz5%! @im a ATTORNEYS BY United States Patent O M 3,461,788 DEVELOPER TRAYAND SUPPLY TANK ASSEMBLY Emil Tiger, Highland Park, Erskine G. Corman,Forest Park, and Kenneth R. Reich, Downers Grove, Ill., assignors toFormfoto Manufacturing Company, Villa Park, Ill., a corporation ofillinois Filed Oct. 23, 1965, Ser. No. 503,064

int. Ci. G0311 13/04 U.S. Cl. 95-95 22 Claims ABSTRACT F THE DllSCLOSUREA photodeveloping apparatus developer tray and tank assembly comprises amold plastic tank having a bottom wall and upstanding side and front andrear walls integral therewith, and an upstanding curb flange integralwith and joined to the upstanding walls in outwardly loff-set relationby a rim providing an upwardly facing shoulder. `On this shoulder a basestructure of a developer tray is mounted and has an outwardly extendingflange with an edge snapped into a groove in the curb flange. DownwardlyeX- tending pins on the base flange lit into sockets in the shoulder.The tank has an alcove at one side over which is mounted a motor drivinga pump connected by tube to a depending well from which developersolution is delivered to the tray. Small openings drain the tray bottomand larger openings drain a spillover gutter along one edge of the tray.

This invention relates to improvements in means for efficientlydeveloping latent images on electrophotographically charged copy sheetsand employing a liquid toner or developer, and more particularlyconcerns a new and improved developer tray and supply tank assembly.

Among the important objects of the present invention is that ofproviding a new and improved developer tray and supply tank assemblywhich is especially adapted for use in desk model sizes ofelectrophotographic copying machines.

Another object of the invention is to provide a new and improved trayand supply tank assembly which is simple and rugged in construction andis equipped with selfcontained means for maintaining a tray unit and atank unit in assembly.

A further object of the invention is to provide a new and improved trayand tank assembly of the character described having novel snap-inretaining means.

Still another object of the invention is to provide a new and improvedefficient relationship of a liquid developer circulating motor withrespect to a tray and tank assembly.

Yet another object of the invention is to provide new and improved meansfor effecting efficient circulation of liquid toner developer in anelectrophotographic developer tray structure.

Other objects, features and advantages of the present invention will bereadily apparent from the following detailed description of a preferredembodiment thereof taken in conjunction with the accompanying drawing,in which:

FIGURE 1 is a top plan view of a tray and tank assembly embodyingfeatures of the invention;

FIGURE 2 is a vertical transverse sectional detail view takensubstantially along the line II-II of FIGURE 1; and

FIGURE 3 is an enlarged fragmentary sectional detail View takensubstantially on the line lII-III of FIGURE 1.

A supply of liquid developer D is contained within an upwardly openingtray-like tank 5 which is preferably constructed as a synthetic plasticmolding and desirably of a clear, transparent plastic so that thecontents may readily be viewed to` observe liquid level and condition.This tank is desirably of a generally elongated rectangular form havinga bottom 7, opposite end walls 8, a front wall 9 and a rear wall 10. Onthe bottom wall may be provided suitable downwardly extendingreinforcing and supporting base-engaging ribs 11.

On its upper edge as defined by the upstanding side and end walls, thetank 5 is adapted to support a complementary developer tray 12 which isalso preferably constructed of a synthetic plastic material as aone-piece hollow molding having a lateral flat base flange 13 projectingoutwardly entirely thereabout to a length and width slightly greaterthan the length and width dimensions between the outer faces of theupper ends of the side walls 8 and the front and rear walls 9 and 10 sothat the tray 12 can be mounted through the flange 13 directly on top ofand as a closure for the tank 5. For centering the tray flange 13 on thetank the upstanding walls are provided with an upstanding curb flange 14which is offset outwardly from the upper edge of each of the respectivewalls and joined integrally thereto on an offsetting reinforcing rimbead or rib 15. Within its inner face, the curb flange is dimensioned toreceive the edge of the tray flange 13 freely thereinto, being providedwith a slight draft, sloping upwardly and outwardly for this purpose.

Means are provided for self-retaining, snap-in, snap-out interengagementof the flanges 13 and 14 for holding the tray and the tank in assembly.For this purpose, the curb flange 14 is provided on its inner faceadjacent to its root, lower edge with inwardly projecting interlockmeans desirably comprising a shallow rib 17 defining with the rim 15 aninterlock groove 18 within which the edge of the tray flange 13 issnappingly interengageable, being provided with a stiffening interlockbead 19 which engages in complementary interlocking relation with andunder the interlock rib 17. The upper margins of the upright tank walls,together with the curb flange 14 and the rim 15 are suflicientlyresiliently flexible to enable snap-in interengagement of the tray rimedge behind the interlock rib 17 into the groove 18 by yielding of theflange and rib in response to downward camming pressure against theupper cam surface of the interlock rib applied manually to the trayflange 13. Thereafter the tray and the tank are held firmlyinterlockingly interengaged as a unit so that the tank, even with liquidtherein can be manipulated, using the tray as a handle. When it isdesired to separate the tank 5 and the tray 12, the interlock beads 19on the tank flange can be snapped from behind the interlocking rib 17 hygrasping the tray in one hand and flexing the rim 14 progressively awayfrom the tank flange edge as relative separating pressure is appliedmanually between the tank and the tray.

For additional assurance against unintentional yielding of thetray-supporting tank wall portions interlocking pins and sockets areprovided, in a desirable form comprising suitable integral downwardlyprojecting pinlike lugs 20 located at suitable spaced intervals alongthe side and front and rear walls and fitting downwardly into upwardlyopening complementary sockets 21 in the upwardly facing shoulder onwhich the tray flange rests. It will be apparent, that this pin andsocket interengagement resists unintentional outward flexing of theupper margins of the upstanding walls away from the tray flange and thussubstantially supplements and assures the thoroughly interlockedrelationship between the rib 17 and the bead 19 until the curb flange 14is deliberately reflexed to release the interlocked relationship.

Supported entirely by the tray flange 13 is a hollow upstandingrectangular wall structure comprising side walls 22, a relatively shortfront wall 23 and a substantially higher rear wall 24 defining a hollowspace within which is accommodated an integral trough 25 of generallysemi-cylindrical form with its rear edge descending from the top of therear wall 24 and its front edge at about the same elevation as the topof the front wall 23 and merging with the upper rear edge of an overiiowgutter 27 which merges at its front edge with the front wall 23.Respective upstanding end closure panels 28 for the opposite ends of thetrough 25 and the gutter 27 are integral with the side walls 22 of thetray unit. At suitable intervals reinforcing Webs 28 connect the frontupwardly extending wall portion defining the channel of the gutter 27 tothe front wall 23. Similarly, at suitable intervals reinforcing webs 29connect the rear portion of the wall delining the trough 25 with therear wall 24. This affords a substantially rigid tray structure.Additional rigidity is aliorded by respective upper juncture ribs 30 and31 joining respectively the front wall 23 with the gutter 27 and therear wall 24 with the trough 25. Reinforcement is also alforded by therib-like juncture 32 between the upwardly directed curved wall of thetrough 25 and the rear wall portion of the gutter 27.

For limiting contact of a paper sheet S delivered by transport rollers33 downwardly into the rear portion of the trough 25 it is afforded withrelatively sharp peaks 34 on respective ribs 35 which project upwardlyfrom the surface of the wall defining the trough 25 and extend from itsrear edge contiguous to the juncture rib 31 to the front juncture rib32. These ribs 35 also reinforce the structure and enable the tray to bemade in a thin molded section. In order to assure straight travel of theimage carrying paper S downwardly through the tray trough 25, the guideribs 35 are provided in two relatively divergently related sets ofpluralities or spaced series of the ribs as best seen in FIGURE l, thedivergence being from the rear toward the front of the trough. One ofthe series of the ribs 35 extends in diagonal relation from thelongitudinal center of the rear edge toward one end of the trough andthe other series extends diagonally from the longitudinal center of therear edge toward the opposite end of the trough.

Developer solution D is pumped from within the tank into the tray trough25 by means of a pump 37 operated by an electrical motor 38 which isadapted to be connected to an electrical outlet in the associatedcopymaking machine by means of an electrical plug 39 carried on anelectrical cord 40. To accommodate the pump and motor unit convenientlyand in offset relation to the tray 12 so that the motor can be readilycooled and heat therefrom will not tend to heat the solution in thetray, the bottom wall 7 and the front wall 9 of the tank 5 areconstructed to provide an alcove protuberance 41 having an extension 14aof the curb thereon and an extension 15a of the rim shoulder thereonwithin and upon which the motor 38 is mounted, with the pump 37 housedwithin the alcove which opens into the tank chamber for free accessthereinto of the developer solution in the tank.

From the pump 37 the solution is conveyed through a flexible conduit 42to the trough 25 in a manner which will avoid surging or splashing ofthe solution. To this end, the delivery end of the conduit 42 isconnected into a delivery well 43 which opens upwardly into the bottomof the trough, desirably adjacent to one end thereof. This well isformed as an integral downwardly extending hollow upwardly openingboss-like protuberance on the trough 25. Mounting of the delivery endportion of the flexible hose 42 is effected by a projection of such endportion through aligned openings 44 in the opposite side walls definingthe well protuberance, with the end of the hose closed by a plug 45, andthat portion of the hose which bridges across the inside of the wellhaving a large discharge port 47. To effect smooth, relatively unroiledWelling up of the delivered developer solution, means are mountedgenerally opposite the delivery discharge opening or port 47,conveniently in the bottom of the Well and desirably comprising severallayers of woven open mesh material 4S, of which a line wire screen meshis suitable. To avoid stagnation of solution or developer or 4 tonerparticles in the bottom of the well, a small drain hole 49 (FIG. 2) isprovided in the bottom of the well protuberance and of such relativelysmall flow area ratio to the delivery port 47 as to be insignificant indiverting developer solution from the trough 25 while the pump 37 is 1noperation.

As visualized in FIGURE 2, while the pump 37 is operating, acontinuously circulating quantity of the developer D is maintained inthe trough 25 at a level determmed by the height of the rib 32 whichserves an overflow lip from which the overiiowing solution drops intothe gutter 27 and thence discharges downwardly into the sump of the tank5 through respective return ports 50 located closely adjacent to theopposite ends of the trough whereby the returning solution, from whichdeveloper toner has been removed in the development of latent images onthe copy sheets transported through the developer tray, will be enrichedon sweeping from the opposite sides of the tank toward the pump 37 inthe recirculation cycle. Stagnation of solution and more particularlyany toner that may possibly precipitate into the bottom of the trough 25is avoided by small drain holes 51 located at suitable intervals alongthe low point in the trough declivity, at least one such hole 51 beingprovided Within each of the trough areas subdivided by the contactlimiting and guide ribs 35.

Guidance of the copy sheets S from the front edge of the developmenttrough 25 is in a direction upwardly and forwardly over the overflow liprib 32 into the nips of driven squeeze rollers 52 which form part of thetransport system for the copy sheet. Surplus solution carried upwardlyout of the developer trough squeeze from the sheet by the rollers 52drops therefrom into the gutter 27.

Should any developer solution splash out of or otherwise escape from thetrough 25 or gutter 50, it will collect in the gutter defined betweenthe walls of the tray 12 by the surrounding lateral supporting flange 13and the curb flange 14. From this emergency gutter any escaped solutionmay drain back into the sump of the tank through a large iiller opening53 provided in the rear, wider portion of the ange 13. This opening isalso conveniently located to receive a funnel or supply hose or nozzleof a supply receptacle from which a replenishing supply of solution ordeveloper and toner powder can be poured into the tank.

Because the pump 37 and the motor 38, and particularly the latter, eventhough of as miniaturized a form as practicable, provide a mass ofsubstantial weight which, in effect, is hung on the front wall 9, withthe bulk of such weight residing in the motor and located adjacent tothe curb 14 and the rim 15, there may be a tendency when the assembly islifted through use of the tray 12 as a handle, for the iiange 14 and therim 15 to iiex outwardly on the front Wall 9 and more particularly inthe vicinity of the alcove 41 and thus unintentionally disconnect thebeaded edge of the flange 13 therefrom. Therefore, auxiliary orsupplemental retaining means are desirably provided comprising, in asimple form a plurality of retaining clips each of which has anarrow-U-shaped gripper portion 54 straddling and gripping within itsjaw the upstanding curb ange 14 with an inwardly struck biting lingerprong 55 at each side of the outer or free leg of the jaw firmly holdingthe spring clip in place. Each of the clips also has a tray iiangeholding shoulder loop portion 57 which, in the assembly, thrustsdownwardly against the iiange 13 and lockingly opposes the interlockbead 19 thereon. These retaining clips are easily applied at a pluralityof locations longitudinally along the top of the Wall 9, and especiallyat both sides of the motor 38 by orienting the gripper jaw portions 54with the top of the flange 14 and pressing downwardly until the shoulderloop 57 of the clip comes to a stop against the top of the flange 13, inwhich holding, and tiange locking relationship the clip is automaticallyretained by action of the biting prongs 55 which dig into the mountingflange 14. In addition to their iiange locking function,

the clips may serve as means for retaining the electrical cord 40 andavoid the straining connections of the cord to the motor 38. For thispurpose the cord is readily inserted in the shoulder loop S7 of theselected clip or clips.

Additional means for retaining the assembled orientation of the rim 1Sand the flange 13 along the tank front wall 9 and the tray front wall 23comprises a base plate 58 mounting the motor 38 and which rests on theshoulder provided by the alcove rim a which is downwardly offsetrelative to the rim 15 about equal to the thickness of the plate 58 sothat a substantial margin width of the plate can and does projectinwardly in underlying contiguity to the flange 13. An interlockedrelationship is afforded by a downwardly projecting integral pin-likeboss 59 on the underside of the flange 13 extending into and through asuitable socket hole 60 in the underlying portion of the plate 58. Alongthe outer margin of the plate 58 and more particularly adjacent to eachopposite corner thereof an upstanding respective pin-like interlock bossprojection 61 integral with the rim flange 15a fits into and through asocket hole 62 in the plate. Additionally, each of the three sections ofthe curb flange 14a desirably has an individual horizontal interlock rib63 which snappingly engages over the adjacent edge portion of the flange58 as permitted by resilient flexibility of the curb flange 14a. Throughthis arrangement the motor mount flange 58 is held efliciently againstunintentional displacement, but may be easily snapped into mountedposition or snapped out of mounted position, and in the mounted positionand in assembly with the developer tray cooperates with the tray toretain the adjacent portion thereof substantially against displacementand in turn is further interlockingly retained by the tray and theretaining clips.

It will be understood that various modifications may be suggested by theembodiments disclosed, but We desire to claim within the scope of thepatent warranted hereon all such modifications as come within the scopeof our invention.

We claim as our invention:

1. In combination in a photodevelopment apparatus of the characterdescribed:

a molded plastic tank having a bottom wall and upstanding side and frontand rear walls integral therewith;

an upstanding curb flange integral with and joined to said upstandingwalls in outwardly offset relation by a rim providing an upwardly facingshoulder;

a developer tray above said shoulder and having a base structure mountedon said shoulder; and

snappingly coactive and separable integral retaining means on said curbflange and on said base structure.

2. Apparatus as defined in claim 1, in which said means include aninwardly opening groove in said curb flange alongside said shoulder, andsaid base structure comprises an outwardly extending flange having anedge in said groove.

3. Apparatus as defined in claim 2, in which said groove is defined by arib spaced from said shoulder.

4. Apparatus as defined in claim 2, in which said edge has a bead whichengages in said groove.

5. Apparatus as defined in claim 1, comprising, in addition, pin Iandsocket means on said base structure and said rim supplementing saidretaining means.

6. In combination in photodevelopment apparatus of the characterdescribed:

a developer tray having a base;

a developer supply tank opening upwardly and having shoulder meansthereon on which said tray is retainingly seated;

means defining an alcove opening into the tank and upwardly outwardlyrelative to said shoulder; and

an electrical motor mounted on said alcove means and having a developerpump within said alcove means and communicating with said tray to pumpdeveloper from the tank into the tray.

7. Apparatus as defined in claim 6, in which a flexible tube leads fromsaid pump, and said developer tray has thereon well-defining meansopening upwardly thereinto and said tube is connected to discharge intothe well.

8. Apparatus as defined in claim 6, in which said alcove defining meansand said motor have means snappingly interengaged for retaining themotor and pump in assembly therewith.

9. Apparatus as defined in claim 6, in which said motor and said trayhave means interengaging to assist in mutual retention thereof in theassembly.

10. Apparatus as defined in claim 9, including retaining clipssupplementing said motor and tray retaining means in retaining the tankand tray and motor in assembly.

11. In combination in photodevelopment apparatus of the characterdescribed:

an upwardly opening developer tank having an upwardly facing upper endsupporting shoulder;

a developer tray extending above said tank and having a lower endportion lateral base flange seated on said shoulder; and meansreleasably retaining the flange on said shoulder including retainingclips holding the flange against unintentional upward displacement fromsaid shoulder.

12. In combination in photodevelopment apparatus of the characterdescribed:

a developer tank opening upwardly;

a developer tray providing an upwardly opening trough and seated on andclosing said tank;

a pump carried by said tank and having a delivery tube extendingtherefrom; and

means defining a downwardly extending Well opening upwardly fordischarge into said trough and having said tube in deliverycommunication therewith.

13. Apparatus as defined in claim 12, including means in said well toeliminate roiling.

14. In apparatus of the character described:

a developer tray comprising a base having upstanding walls andsupporting within said walls an upwardly opening trough and an upwardlyopening gutter along the edge of said trough and lower than the rearedge of the trough;

two spaced series of paper limiting and guide ribs in said troughextending from and between said edges and with one series extending indiagonal relation from the longitudinal center of said rear edge towardone end of the trough and the other series extending diagonally from thelongitudinal center of said rear edgel toward the opposite end of thetrough;

said trough having an opening thereinto for delivery of developersolution;

small drain holes in the bottom of the trough in al1 of the between ribareas; and

respective large sized drain openings at the opposite ends of saidgutter.

1S. In combination in photodevelopment apparatus of the characterdescribed:

an upwardly opening developer tank having an up- Wardly facing upper endsupporting shoulder;

a developer tray extending above said tank and having a lateral baseflange seated on said shoulder; and

means releasably retaining said base flange on said shoulder;

said base flange being at least in part of substantial width and havinga filler and drain opening therethrough to the inside of the developertank.

16. In apparatus of the character described:

a developer tray comprising an upwardly opening trough and an upwardlyopening gutter along a front edge of said trough and lower than a rearedge of the trough;

spaced paper limiting and guide ribs in said trough extending from andbetween said edges and having areas of the trough therebetweensubstantially lower than the ribs;

said trough having an opening thereinto for delivery of developersolution;

said areas between the ribs having small drain holes;

and said gutter having a drain opening therein.

17. Apparatus according to claim 13, said delivery tube discharginggenerally downwardly into said well, and said means to eliminate roilingcomprising open mesh material in the bottom of the well.

18. For use in the development of latent images Onelectrophotographically charged copy sheets and employing a liquiddeveloper, a developer tray and supply tank assembly, comprising:

a developer supply tank having an upward opening;

a developer tray mounted on said tank over said opening and having anupwardly opening trough having a rear edge and a front edge and adaptedto receive successive sheets from transporting means along its rearedge, and a gutter along and below the front edge of the trough andadapted to be located under squeeze rollers into which copy sheets aredirected from the trough, said gutter having drain opening therefromdischarging through the tank opening into the tank;

and means carried in assembly with the tank for supplying developersolution from the tank into said trough so that copy sheets passingthrough the trough will be treated with the solution and said squeezerollers will squeeze excess solution from the copy sheets into saidgutter.

19. In combination in photodevelopment apparatus of the characterdescribed:

an upwardly opening tank for developer solution;

a developer tray mounted on said tank and comprising an upwardly openingtrough having an arcuate bottom between a rear edge and a front edge;

spaced paper limiting and guide ribs integral with said tray and locatedin said trough and extending from and between said edges, with areas ofthe trough between the ribs substantially lower than the ribs;

and means for delivering developer solution from the tank into saidtrough;

said areas between the ribs having small drain holes therethrough fromthe trough into the tank to avoid stagnation of developer solutionbetween the ribs.

20. In combination in photodevelopment apparatus of the characterdescribed:

an upwardly opening developer tank having an upstanding wall structurethereabout provided on its upper end with an upwardly facing shoulder;

a curb flange around said shoulder and olset outwardly relative to saidWall structure;

a developer tray having a trough with downwardly extending wallstructure having laterally extending liange structure thereon seated onsaid shoulder;

means removably securing said ange to said shoulder;

and means for delivering developer solution from said tank into saidtrough.

21. In combination in photodevelopment apparatus of the characterdescribed:

a molded plastic developer supply tank opening upwardly and having anupwardly facing shoulder including upwardly opening sockets therein;

a molded plastic developer tray having a laterally outwardly extendingand downwardly facing flange including downwardly extending pinsengageable in said sockets;

said tank having inwardly opening groove-defining means integral withsaid shoulder; and

said flange of the tray having an edge snappingly separably engageablewith said groove-delining means.

22. A photodevelopment apparatus developer tray construction comprising:

upstanding wall structure supporting a development trough and aspillover gutter along one edge of the trough; and

a downwardly extending well protuberance having an opening upwardly intosaid trough and adapted to have connected therewith a developer solutionsupply duct;

said well protuberance having a drain opening in the bottom thereof.

References Cited UNITED STATES PATENTS 2,747,482 5/1956 Gacki et al.95--96 2,593,998 4/1952 Dupuis 220-97 X 2,916,161 12/1959 Schaefer220-97 X 2,286,351 6/1942 Drucker 95--97 3,070,275 12/ 1962 Bostrom220--17 3,203,336 8/1965 Limberger 95-89 FOREIGN PATENTS 282,062 12/1964 Netherlands.

NORTON ANSHER, Primary Examiner CHARLES E. SMITH, Assistant ExaminerU.S. Cl. X.R. -89

